MASH was one of the most popular TV shows of all time, and the members of the 4077th became well known and beloved characters to the entire country.
After more than a decade, people did want to know what happened to all of them after the war. Did Klinger find Soon-Lee's family? How did Radar fare back on the farm? Did Mulcahy get his hearing back? It would have made a fine TV movie, or maybe even a miniseries to have a big reunion of the 4077th stateside after the war (like they talked about doing a few times during the series). See that Klinger found his wife's family and they moved back to the US, only to face racism and discrimination, and is down on his luck as a petty crook trying to make ends meet. Show that Radar's farm had failed and and moved away to join the police in St. Louis. Show that Col. Potter now runs a Veteran's Hospital, and that Hawkeye went home to Maine and a small-town practice. Show that Mulcahy's hearing has been largely restored through surgery. It could have been a huge hit just to see them all later, as a epilogue to the whole story of MASH.
Instead, we got AfterMASH, which took the basic idea of "what happened next" and ran it into the ground. We got three familiar characters: Potter, Klinger and Mulcahy, a brief introduction on how they got there, and then try to replicate MASH stateside. Create a whole new set of young mischievous doctors for Potter to keep an eye on, a whole new bossy administrator to yell at Klinger, and then find thin reasons for constant guest appearances by former MASH cast. It kept trying to be essentially a stateside remake of MASH, with some of the same characters, but the chemistry wasn't there. If not for the MASH name I doubt it would have even lasted as long as it did.
